This circuit was obtained in an American documentation from the 80's. The transistors can be equivalent to those indicated and the crystal can reach a few tens of megahertz.
This circuit is from an old manual, but can be easily assembled as the integrated one is still...
The simple transistor test shown in the figure can be powered by a 9V battery. The test is for...
This regulator can use BD'136 as the main transistor and as a reference next to a BC548 zener. The...